user
Task: Explain the differences between fossil fuels and renewable energy sources.


assistant
Fossil fuels are non-renewable sources of energy, meaning they can't be replenished and will eventually run out. Fossil fuels are also a major source of air pollution since they produce high levels of pollutants when burned. Renewable energy sources, on the other hand, are replenishable and don't cause air pollution. Examples of renewable energy sources include wind, solar, geothermal, and hydropower.